Exploring the Working Principles and Pros and Cons of Common Punch Feeders

Feeders are essential auxiliary devices for achieving automation in punch press operations. With a wide range of punch press types, material applications, and diverse processing techniques, various feeder types have emerged to cater to specific manufacturing needs. This article will explore the working principles of three commonly used feeder types: air, roller, and NC servo feeders. By understanding the characteristics and advantages of each class, you can make informed decisions when selecting the appropriate feeder for your punch press operations.

Air Feeders

Also known as pneumatic or air-powered feeders, air feeders operate on a principle similar to that of medical syringes. These feeders utilize external compressed air to power the downward movement of the feed rod mounted on the punch press slide. The controlled movement of compressed air, directed by a five-hole valve, enables intermittent feeding.

Advantages of Air Feeders

The price is affordable, and the automatic production of punching machines can be realized with a small investment.

Disadvantages of Air Feeders

  1. Although the air feeder offers cost-effective automation for punching machines, it must be noted that it operates at a slower feeding speed. This limitation arises from the external air source’s constrained pressure and flow rate, making it more suitable for low-speed punching machines.
  2. The air feeder exhibits limitations regarding feed accuracy, which can be both poor and unstable. This is attributed to its pneumatic push-type working principle, where the material is simultaneously clamped and pushed. As a result, there is a risk of material being pushed and fed before complete clamping, leading to unpredictable sliding and diminished feeding accuracy. Additionally, the air feeder comprises various vulnerable components, including O-rings and seals, which can result in faults such as air leakage when not adequately maintained, causing instability in the machine’s operation.
Air feeder

Roller Feeders

The roller feeder is also referred to as a mechanical feeder. It utilizes the punch press’s output shaft to drive a pull rod, which pulls the roller’s rocker arm. In conjunction with a transmission shaft, the rocker’s arm converts the reciprocating motion of the drive shaft into a unidirectional feeding movement of the feeding roller. Notably, the roller feeder provided by our company is equipped with a brake device to ensure the feeding roller remains stationary and prevents any backward movement.

Advantages of Roller Feeders

High-cost performance, no need for additional air source and power supply, high mechanical transmission stability, and low failure rate.

Disadvantages of Roller Feeders

  1. After the feeding step stops, adjust the eccentric disk installed on the output shaft of the punch press, and it needs to be adjusted several times to calibrate.
  2. Limited installation flexibility, with strict material width, thickness, and feeding step distance restrictions.
Mechanical Roll Feeder

NC Servo Feeders

Also known as NC numerical control feeders,  NC servo feeders employ a servo motor to drive the feeding roller’s movement. Control of the servo motor is facilitated through a touchscreen interface and PLC system.

Advantages of  NC Servo Feeders

  1. User-friendly operation via the touchscreen interface, allowing for easy setup and adjustments.
  2. Versatility and high customization cater to various applications and offer precise feeding accuracy.
  3. Excellent stability and the ability to handle materials of any length.

Disadvantages of  NC Servo Feeders

  1. Relatively higher cost than air and roller feeders due to the adoption of servo motor technology.
  2. Slower feeding speed due to servo system response, making them less suitable for high-speed feeding requirements.
RNC Servo Roller Feeder


Choosing the right feeder type for punch press operations is crucial for achieving automation, efficiency, and production optimization. Understanding the working principles, advantages, and disadvantages of different feeder types, such as air feeders, roller feeders, and servo feeders, empowers you to make informed decisions that align with your manufacturing needs. Invest wisely in the right feeder solution, and you’ll enhance productivity and stay ahead in today’s competitive manufacturing landscape.